At the time of admission of a new partner, general reserve appearing…

The correct answer is Option (3) → Old Partner's Capital accounts

A general reserve in the old balance sheet is profit earned and kept back before the new partner joined. It belongs to the old partners, so it is transferred to their capital accounts in the old profit sharing ratio.

Option (1) All partner's Capital accounts — Incorrect. The new partner has no claim on profits earned before his admission.

Option (2) New partner's Capital account — Incorrect. The reserve was not earned in his time at all.

Option (4) Sacrificing Partner's Capital accounts — Incorrect. The sacrificing ratio is used for goodwill; reserves go to all old partners in the old ratio.